Lutjanus russellii

Lutjanus russellii goes by several common names, including Russell's snapper, Moses snapper, fingermark bream, Moses seaperch, and Russell's sea-perch. This marine ray-finned fish belongs to the snapper family Lutjanidae and is found in the western Pacific Ocean.

Taxonomy

The species was first formally described in 1849 by Dutch physician and ichthyologist Pieter Bleeker, who named it Mesoprion russellii. The type specimen came from Jakarta, Java, in Indonesia. Its specific name honors Patrick Russell, a Scottish surgeon and herpetologist who illustrated the fish in 1803 without formally naming it. Within the genus Lutjanus, this species is most closely related to the Indian Ocean Lutjanus indicus.

Description

The body of Lutjanus russellii ranges from moderately deep to slender, with a standard length about 2.6 to 2.8 times its depth. The forehead may be steep or moderately sloped, and the preopercle has poorly developed knob and incision. The vomerine teeth form either a triangular patch with a rearward extension or a rhombus shape, and there is a small patch of tiny teeth on the tongue.

The dorsal fin has 10 spines and 14 soft rays, while the anal fin has 3 spines and 8 soft rays; both fins have rounded rear edges, though the anal fin tip can be pointed. The pectoral fins have 16 to 17 rays, and the caudal fin is either truncate or weakly emarginate. Maximum total length is 50 cm (20 in), though 30 cm (12 in) is more typical. Coloration is whitish to silvery greyish-pink with a brownish back.

An indistinct black spot, sometimes very faint, appears on the lateral line below the front part of the dorsal fin. The dorsal and caudal fins are reddish, while the other fins are yellow. Juveniles are white with four brown to blackish longitudinal stripes along the flanks (which may be interrupted) and a horizontally elongated black spot or ocellus on the lateral line.

Distribution and habitat

This species mainly occurs in the western Pacific, from the Gulf of Thailand and Sumatra east to Tonga, north to southern Japan, and south to Australia. In Australian waters, it ranges from Shark Bay and offshore reefs in Western Australia, Ashmore Reef in the Timor Sea, around the northern and eastern coasts down to Wollongong, and possibly to Jervis Bay in New South Wales. It inhabits depths between 3 and 80 m (9.8 and 262.5 ft) on offshore coral reefs as well as inshore rocky and coral reefs.